Secondary Plane Biomechanics of Iliotibial Band Syndrome in Competitive Female Runners

Abstract

Iliotibial band syndrome (ITBS) is the second leading cause of knee pain in runners and is the number one cause of lateral knee pain. The mechanisms by which runners develop ITBS are still poorly understood with few investigations looking at the contribution of the frontal and transverse planes of motion. It has been suggested increased motion in these planes would place greater tension on the ITB and result in ITBS over time. PURPOSE: To retrospectively examine the biomechanical differences between a control group with no history of ITBS, and a group who have previously sustained ITBS in the past. It was hypothesized that runners who had previously sustained ITBS would exhibit greater peak rearfoot eversion (RFEV), knee internal rotation (KIR), hip adduction (HADD), and hip internal rotation (HIR) angles. In addition greater knee frontal and transverse moments (KMOMY, KMOMZ) at initial impact peak of vertical ground reaction force were expected. METHODS: 35 female runners, between the ages of 18–45 who have previously sustained ITBS, were recruited for the study. 35 age and mileage match female runners who had never had any hip or knee injuries, served as the controls. Subjects ran along a 25M runway at a speed of 3.7 m/s. Data from 5 trials were averaged for analysis using One tail independent t-test's for group comparisons (p <0.05). RESULTS:TableThe ITBS group exhibited significantly greater KIR and HADD peak angles and greater KMOMY and KMOMZ compared to controls. CONCLUSIONS: These data suggest that repetitive exposure to increased joint motion and loading over time would require greater restraint from the ITB and result in the cascade of events that cause ITBS. Prospective studies are necessary to more fully determine if these running biomechanics are predictive of future injury.